There are several types of glaucoma. The two main types are open-angle and angle-closure. These are marked by an increase of intraocular pressure (IOP), or pressure inside the eye.
Open-angle glaucoma, the most common form of glaucoma, accounting for at least 90% of all glaucoma cases, is caused by the slow clogging of the drainage canals, resulting in increased eye pressure. It has a wide and open angle between the iris and cornea, develops slowly and is a lifelong condition, and has symptoms and damage that are not noticed. “Open-angle” means that the angle where the iris meets the cornea is as wide and open as it should be. Open-angle glaucoma is also called primary or chronic glaucoma. It is the most common type of glaucoma, affecting about three million Americans.
Angle-closure glaucoma, a less common form of glaucoma: It is caused by blocked drainage canals, resulting in a sudden rise in intraocular pressure, has a closed or narrow angle between the iris and cornea, develops very quickly, has symptoms and damage that are usually very noticeable, and demands immediate medical attention. It is also called acute glaucoma or narrow-angle glaucoma. Unlike open-angle glaucoma, angle-closure glaucoma is a result of the angle between the iris and cornea closing.
Normal-Tension Glaucoma (NTG) or low-tension or normal-pressure glaucoma is where the optic nerve is damaged even though the eye pressure is not very high. Congenital Glaucoma occurs in babies when there is incorrect or incomplete development of the eye's drainage canals during the prenatal period. This is a rare condition that may be inherited. When uncomplicated, microsurgery can often correct the structural defects. Other cases are treated with medication and surgery. Other Types of Glaucoma include: Secondary Glaucoma, Pigmentary Glaucoma, Pseudoexfoliative Glaucoma, Traumatic Glaucoma, Neovascular Glaucoma, Irido Corneal Endothelial Syndrome (ICE), and Uveitic Glaucoma.
Open angle glaucoma is the most common form of glaucoma, affecting about three million Americans. It happens when the eye's drainage canals become clogged over time. The inner eye pressure (intraocular pressure or IOP) rises because the correct amount of fluid cannot drain out of the eye. With open-angle glaucoma, the entrances to the drainage canals are clear and should be working correctly. If open-angle glaucoma is not diagnosed and treated, it can cause a gradual loss of vision. This type of glaucoma develops slowly and sometimes without noticeable sight loss for many years. It usually responds well to medication, especially if caught early and treated.
Vision loss in glaucoma, a neurodegenerative disease that is the leading cause of irreversible blindness worldwide, is due to the dysfunction and death of retinal ganglion cells (RGCs). Current therapies all act by lowering intraocular pressure (IOP). However, pressure reduction can be difficult to achieve, and even with significant pressure lowering, RGC loss can continue. Efforts have therefore been made to develop neuroprotective agents that would complement IOP-lowering by directly inhibiting the RGC cell death process, though no neuroprotective agent is yet in clinical use.
It is an object of the invention to provide methods for encapsulation or incorporation into polymeric matrices, including nano- and micro-particles, with increased loading, of drugs for treatment of glaucoma and neuronal damage.
It is still another object of the invention to provide improved dosage formulations, prolonged pharmacokinetics, and methods of use thereof.